Daniel Ray Carter Jr., a sheriff's deputy in Virginia, claims he was fired because he "Liked" a Facebook post belonging to the political rival of his own boss. When he fought the firing in court, the judge ruled against him saying that clicking the "Like" button isn't protected speech: "It is not the kind of substantive statement that has previously warranted constitutional protection."
The case presents an interesting dilema.
On one hand, I hope we're reaching the point where most people understand that clicking the Facebook "Like" on a statement, article or page is not the equivalent of an endorsement of all the things that article/page/group stands for.